Although ample evidence has documented sex differences in the course of drug addiction, neuroendocrine contributions to these sex differences have not been fully explored. Oral contraceptive pills are used by the majority of women in the US for at least one period of their reproductive years, and dramatically decrease sex hormone levels. However, any potential relationship between oral contraceptives and drug abuse/dependence that may relate to or explain previously observed sex differences has never been formally investigated to our knowledge. We hypothesize that the change in hormones caused by oral contraceptive use can decrease performance on an emotion regulation task that activates regions of the brain previously shown be less active in oral contraceptive users. Deficits in emotion regulation have been linked to substance abuse problems. Therefore, we propose to investigate whether oral contraceptives decrease emotion regulation as a first step toward determining whether they can influence efforts toward drug abstinence.